Ion-producing device



c-18, 1910 HWM'HN'KE 6, 1

ION-PRODUCING DEVICE Filed March 19, 1968 I lnrenlar: #r ee/1 2 Horwe United States Patent O 3,546,451 ION-PRODUCING DEVICE Herbert Jahnke, Unterthingau, Allgau, Germany, assignor to Constantin Graf von Berckheim Filed Mar. 19, 1968, Ser. No. 714,288 Claims priority, application Germany, Mar. 20, 1967, B 91,695 Int. Cl. H013 37/.08

US. Cl. 250-43 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF THE INVENTION The present invention relates generally to the production of ions in air, and more particularly to the production of unipolar ions. Still more specifically, the present invention relates to a device for the production of unipolar ions for electrical environment control in enclosed spaces.

It is well known that human well being and efficiency are governed to a large extent by the content of oxygen ions in the ambient air. The role of ultraviolet radiation in the production of such oxygen ions is also well known as is the fact that the air outside of enclosed areas, and particularly in mountainous terrain, contains a high proportion of oxygen ions because of the ever-present natural ultraviolet radiation.

However, in enclosed spaces such natural ultraviolet radiation is not present and accordingly the production of ions generally is low in such air in such enclosed spaces. Moreover, the negative oxygen ions in enclosed spaces tend to dissipate their charge to the surfaces bordering the enclosed space with the result that the air in an enclosed space loses its content of negatively charged oxygen ions so that the content of positively charged carbon dioxide ions becomes preponderant. A further factor which adversely affects the 'ion content of air in an enclosed space is the fact, if the air is contaminated with a relatively high percentage of floating particulate contaminants, such as dust, as is very frequently the case, the small ions will rather quickly yield their charge to the particulate contaminants.

All of this being well understood, it has been proposed to produce ions artificially in the air of enclosed spaces. This has been attemped by means of radioactive substances, artificial ultraviolet radiation or corona discharge. All these approaches suffer from disadvantages. Specifically, the use of radioactive substances always brings with it a certain danger because the radiation emitted by such substances cannot be terminated at will, and is there fore continuous. While it is true that such radiation can be shielded, it is equally true that this requires significant economic expenditures and makes it diflicult if not completely impossible to utilize such substances for the purposes at hand freely in various different rooms and whenever desired. Substantially the same problems obtain with utilization of artificial ultraviolet radiation. Here, again, it is difiicult to shield persons present in an enclosed space wherein such radiation is utilized, against undesirably high incidents of ultraviolet radiation. Finally, it has also been 3,546,451 Patented Dec. 8, 1970 found that both in the case of artifically produced ultraviolet radiation and in the case of corona-discharge ionizing arrangements it is impossible to suppress the production of ozone and nitrous oxides, both of which are damaging to the human organism over a period of time at such relatively high concentrations as occur under these circumstances.

It is thus a general object of the present invention to provide an arrangement for the production of unipolar air ions which is not subject to the aforementioned disadvantages.

A further object of the invention is to provide such an arrangement which is simple and inexpensive to construct.

An additional object is to provide an arrangement of the type here in question which eliminates or at least reduces to an absolute minimum, the undesirable side effects mentioned above.

SUMMARY OF THE INVENTION In accordance with one feature of my invention I provide, in a device for producing unipolar ions in air, an electrically excitable source of visible and ultraviolet electromagnetic radiation. This source is at least in part bounded by a wall consisting of vitreous material, permeable to the emitted radiation. An electrically energizable electrode means is associated with the source and includes a plurality of resilient filament portions having free ends exteriorly engaging the wall. Thus, when the electrode means is energized, an electrostatic field is established in the region of the aforementioned free ends and the emission of ultraviolet electromagnetic radiation from the aforementioned source, coupled with the establishment of this electrostatic field, results in the production of ions in the ambient air.

The source of electromagnetic radiation is advantageously a conventional gas discharge tube the inside of whose glass wall may or may not be coated with a lightemitting substance, such as the fluorescent or phosphorescent metallic salts which are well known in the art.

A device constructed in accordance to the present invention produces significant amounts of unipolar air ions without, however, producing ozone or nitrous oxides. Furthermore, it does not produce objectionable radiation in the area within which the ions are produced. It is well known, of course, that a normally operated conventional gas discharge tube will produce a certain amount of ultraviolet radiation. However, this radiation is confined to the immediate vicinity of the tube and is not normally sufficient to produce ions. Rather, it simply effects increased excitation of the molecules. It, now, the electrode according to the present invention is energized, then a strongly non-homogenous electric field is established at the ends or tips of the electrically conductive filaments of the electrode which engage the glass wall of the tube only with respective very small surface areas. The maximum strength of this field can be determined very precisely by selecting the desired rectification. Relatively small field strengths are sufficient for effecting the desired ionization in conjunction with the molecular excitation produced by the presence of the ultraviolet radiation emitted by the gas discharge tube. The so-called quiet discharge phenomena which occur in this case can be maintained at such low levels that it is possible to suppress the production of ozone and nitrous oxides as well as of radiation frequencies which produce radio-Wave interference and which normally occur during corona discharge at high field strength, can be suppressed completely, or to a minimum, at which they become insignificant and are no longer of concern.

I have also found that the vibrations occurring in the gas discharge tube as a result of the gas discharges taking place therein effect minute mechanical vibration of the electrode filaments, a phenomenon which, on the one hand, varies the configuration and strength of the electric filed and which on the other hand provides in effect a mechanical acceleration of the surrounding air molecules so that a constant flow of new molecules becomes subjected to the ionization treatment.

It is particularly advantageous if the inside of the glass wall of the gas discharge tube is coated with a light-emitting substance, such as fluorescent or phosphorescent metallic salts, in the well known manner. Such coating partially absorbs the ultraviolet radiation produced by the tube and thus further serves to limit the influence of this ultraviolet radiation to the immediate vicinity of the tube exterior. Furthermore, this use of conventional gas discharge tubes results in a very economical construction of the device according to the present invention because stack tubes can be utilized whose cost is relatively low.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a side-elevation of an arrangement embodying my invention;

FIG. 2 is a cross-section through the embodiment of FIG. 1; and

FIG. 3 illustrates a circuit for use with the embodiment illustrated in FIGS. 1 and 2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Discussing now the drawing in detail, and firstly FIGS. 1 and 2 thereof, it will be seen that the electrically conductive electrode is provided in form of a rod-shaped element 1. Of course, this is not the only configuration which is suitable but it is particclarly advantageous because of the simple manner in which it can be connected to the discharge tube. The electrode 1 is provided with a plurality of filamentary wire tips 2 consisting of a suitable material, such as steel wire, and it will be understood that these wire tips 2 must be hair-fine. Spring clamps 3, each comprising two arms 4 and a connecting bight 5, serve to clampingly and releasably connect the electrode element 1 to a conventional gas discharge tube 6. In the illus trated embodiment this gas discharge tube 6 is assumed to consist of a cylindrical glass wall or body 7 whose inner side is coated with a light-emitting layer 8 of suitable material. This construction, and the material for the layer 8, are of course well known and will not be further described. Each end of the gas discharge tube 6 is provided with an electrode 9 having two terminals 10, 10 or 11, 11. It will be noted particularly from FIG. 2, that the clamps 3 are so constructed and configurated, as is the electrode 1 that the clamps 3 will so bias the electrode 1 towards the body of the gas discharge tube 6 that the resilient wire tips 2 are lightly biased into engagement with the outer surface of the cylindrical glass body 7.

The circuit arrangement illustrated in FIG. 3 shows an electrode 1 is connected with a source 13 of direct current via a high ohmic resistor 12. The source 13 advantageously will have a potential of approximately 2,000 volts. While one pole of the source 13 is connected in this manner with the electrode 1, the other pole of the source 13 is connected to ground potential. A high-ohmic resistor having a resistive value on the order of 10 ohms may be interposed in circuit between the electrode 1 and the associated pole of source 13.

The gas discharge tube 6, on the other hand, is connected with its terminals 10 via conductors 14, and with its terminals 11 via conductors 15 to a conventional ballast arrangement 16 which is energized from a source 17 of alternating current. This source may of course be the conventional net current of or 220 volts. Reference numeral 18 indicates that the ballast 16 is also grounded.

It is to be understood that in operation of the novel device herein disclosed, a glow discharge takes place in the gas discharge tube 6 so that ultraviolet radiation is emitted. This ultraviolet radiation excites the light-emitting coating 8 and in the course of so doing is partly absorbed. Some of the ultraviolet radiation, however, penetrates to the immediate exterior of the body 7, that is to the outer surface thereof, where the tips of the filaments 2 are in engagement with the body 7. The vibrations which take place within the interior of the gas discharge tube effect similar vibrations in the ends of the very fine hairlike wire filaments 2 with the result that microscopically small corona discharges occur. It is these discharges, coupled with the ultraviolet radiation at the outer surface of the body 7, which result in the production of ions in the ambient air without, however, producing ozone to any appreciable extent. It is known that negatively charged ions are particularly beneficial for the well-being of the human organism. If it is therefore desired to produce negatively charged ions with the device according to the present invention-as would normally be the case-the electrode 1 is connected with the negative pole of the source of direct current 13, whereupon the device will produce only negatively charged ions in the ambient air. The overall result obtained is analogous to the presence of ions in the air of mountainous regions.

From what has just been said, it follows, of course, that if the production of positively charged ions is desired, it is simply necessary to connect the electrode 1 with the positive pole of the source 13, in which case the negative pole of this source is then connected to ground. In other words, this is a reversal of the connection required for obtaining negative ions.

It will also be understood that the device according to the present invention, may, if desired, be combined with an arrangement for producing an electrostatic field in an enclosed space. In fact, the electrode 1 may itself be constructed as a ceiling electrode to be mounted on the ceiling of a room or as a part of such a sealing electrode. This concept of producing an electrostatic field in an enclosed space is already known and is being mentioned here only for the sake of completeness, having no direct connection with the present invention.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of devices, differing from the types described above.

While the invention has been illustrated and described as embodied in a device for producing ions in air, it is not intended to be limited to the details shown since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims:

1. In a device for producing unipolar ions in air, a combination comprising an electrically excitable gas discharge tube constituting a source of visible and ultraviolet electromagnetic radiation and being at least in part bounded by a wall consisting of vitreous material which is permeable to the emitted radiation; a source of alternating current for exciting said tube whereby the same undergoes slight vibrations; electrically energizable electrode means, including resiliently deflectable filament means exteriorly contacting said wall; and a source of direct current having a pole conductively connected with said electrode means whereby, in response to energization of said tube and vibration of the same, momentary displacements of said filament means out of contact with said wall caused by the vibrations of said tube will result in minute corona discharges between said filament means and said wall while the former is out of contact with the latter.

2. In a device as defined in claim 1, said wall being a tubular casing of said gas-discharge tube and having an inner side coated with a substance adapted to emit light and to partially absorb ultraviolet radiation upon excitation of said tube.

3. In a device as defined in claim 1, wherein said electrode means comprises a rod-shaped portion extending along said tube exteriorly thereof, said filament means being provided on said rod-shaped portion and engaging said wall.

4. In a device as defined in claim 3; and further comprising spring-clip means operative for releasably mounting said electrode means on said tube.

5. In a device as defined in claim 4, wherein said springclip means comprises a plurality of spring-clip members each having two arms arranged to embrace said tube, and a connecting portion extending between said arms and adapted to engage said rod-shaped portion of said electrode means for holding the same in predetermined position relative to said tube.

6. In a device as defined in claim 1; and further comprising ballast means operatively associated with said tube and being connected with another pole of said source of direct current.

7. In a device as defined in claim 6, wherein said other pole and said ballast means are both connected to ground.

8. In a device as defined in claim 1; and further comprising a high-ohmic resistor having a resistive value on the order of 10 ohm and being interposed in circuit between said pole and said electrode means.

9. In a device as defined in claim 1, wherein said filament means comprises a plurality of discrete filaments.

10. In a device as defined in claim 9, wherein said filaments have respective free ends which exteriorly engage said wall.

References Cited UNITED STATES PATENTS 1,965,187 7/1934 Hartman 25043X 2,271,792 2/ 1942 Conant 21-74 3,183,352 5/1965 Brandt et a1 25049.5

WILLIAM F; LINDQUIST, Primary Examiner US. Cl. X.R. 250-495 

